Apparatus for delimbing felled trees

ABSTRACT

An apparatus for delimbing felled trees includes a fixed base, and a pair of blade support bars pivotally connected thereto. Cutting blades are affixed to the blade supports in such a manner that when a tree or a group of trees is pulled through the apparatus, the cutter blades come into limb severing engagement with opposing sides of the tree or trees.

United States Patent [191 Nadeau 1 APPARATUS FOR DELIMBING FELLED TREES [76] Inventor: Georges Nadeau, 167 Golden Avenue Apt. 10, Timmins, Ontario, Canada [22] Filed: Apr. 30, 1973 [21] Appl. No.: 355,735

[30] Foreign Application Priority Data May 4, 1972 Canada 141295 152] -U.S. Cl 144/2. Z [51] Int. Cl. B270 9/00 [581 Field of Search 144/2 R, 2 Z, 3 R, 3 D,

[56] References Cited UNITED STATES PATENTS Susil 144/2 Z 1 Mar.4, 1975 3,074,446 1/1963 Earl l44/2 Z X 3,572,410 3/1971 McElderry 3.672.413 6/1972 .louppl 144/2 Z 3.690.351 9/1972 Strickland et a]. 144/2 2 Primary E.raminer--Andrew R. Juhasz Assistant Examiner-W. D. Bray Attorney, Agent, or FirmCushman, Darby & Cushman [57] ABSTRACT An apparatus for delimbing felled trees includes a fixed base, and a pair of blade support bars pivotally connected thereto. Cutting blades are affixed to the blade supports in such a manner that when a tree or a group of trees is pulled through the apparatus, the cutter blades come into limb severing engagement with opposing sides of the tree or trees.

13 Claims, 10 Drawing Figures PATENTEU 41975 SHE napFg PATENTED 41975 sum 5 n5 5 mdE APPARATUS FOR DELIMBING FELLED TREES BACKGROUND OF THE INVENTION This invention relates to apparatus for delimbing felled trees.

Many highly sophisticated machines have been devised in recent years for delimbing trees and many of these have been very successful. However, most of these machines are quite expensive and thus beyond the reach of very small operators, e.g. very small logging companies, and individuals who may only have use for a delimbing device for a short period of time each P year.

SUMMARY OF THE INVENTION It is an object of the invention to provide a simple yet effective delimbing device for severing the limbs from felled trees.

In accordance with the invention there is provided an apparatus for delimbing felled trees. The apparatus includes a base adapted to be secured in a fixed position and means attached to the base and supporting first and second groups of cutter blades. The cutter blades are arranged to engage and sever limbs from one or more moving tree trunks in engagement therewith. The means supporting the first and second groups of cutter blades are arranged to hold the first and second groups of blades in limb severing engagement with first and second opposing sides, respectively, of tree trunks which, in operation, are moved longitudinally through the delimbing apparatus whereby to sever limbs from said tree trunks.

In accordance with a further aspect of the invention said means supporting said first and second groups of cutter blades comprise first and second cutter blade supports, respectively, to which the cutter blades are affixed, at least one of said cutter blade supports being movable in such a way as to bring the cutter blades thereof into limb severing engagement with one of said opposing sides of the moving trunks and means responsive to movement of the tree trunks for effecting said movement of said one cutter blade support.

In accordance with a further aspect of the invention the means supporting the first and second groups of cutter blades comprise first and second elongated cutter blade supports, respectively, to which said blades are affixed, both of said cutter blade supports being supported for movement relative to said base, and means operatively connecting said cutter blade supports together such that the forces applied to one of said cutter blade supports by virtue of the tree trunk moving while in engagement with the cutter blades thereof tend to cause the other cutter blade support to move such as to bring its blades into limb severing engagement with the other side of said trunk.

In accordance with a further aspect of the invention said other cutter blade support is mounted on an arm for pivotal movement relative to said base.

In accordance with a further aspect of the invention said other cutter blade support is connected at one of its ends to said arm, said cutter blade supports being parallel to one another and being arranged such that they together with said swing arm have a generally open" side defining a loading region whereby to permit felled trees which are to be delimbed to be readily positioned between said cutter blade supports.

BRIEF DESCRIPTION OF THE DRAWINGS In drawings which illustrate an embodiment of the invention:

FIG. 1 is a perspective view of a delimber incorporating the invention;

FIG. 2 is an end elevation view of the delimber in the open position;

FIG. 3 is an end elevation view of the delimber in a fully closed non-operating position;

FIG. 4 is a diagrammatic view illustrating some of the principles of operation of the delimber;

FIG. 5 is a section view taken along line 5-5 of FIG. 1;

FIG. 6 is a view of one of the cutter blade support assemblies;

FIG. 7 is a cross-section view taken along line 77 of FIG. 6;

FIG. 8 is a section view taken along line 8-8 of FIG. 6; and

FIGS. 9 and 10 are somewhat diagrammatic views of portions of a tree engaging roller.

DETAILED DESCRIPTION As best seen in FIGS. 1-3 .the delimber includes a generally flat base 10 of rigid structural steel materials and adapted to lie flat on the ground. Base 10 is adapted to be anchored to the ground via suitable anchorages 12 to prevent movement of the delimber along the ground as trees are pulled through the device in the direction of arrows A in FIGS. 1 and 2 during use.

The delimber includes a spaced apart generally parallel horizontally extending pair of cutter blade supports or bars identified as 14 and 16. The upper blade support bar 16 is pivotally attached to base 10 via an elongated swing arm 18 the upper end of which is rigidly connected to one end of blade support bar 16 and the lower end of which is rigidly connected to pivot rod 20. Pivot rod 20 is rotatably mounted in spaced apart bearings 22 secured to the base 10. A coil torsion spring 24 disposed about pivot rod 20 and co-acting between swing arm 18 and base 10 serves to resiliently bias the swing arm 18 towards an upright position i.e. in the clockwise direction as seen in FIGS. 2 or 3.

The lower blade support bar 14 is also pivotally attached to base 10, and as shown in the drawings, this blade support bar 14 is directly mounted in spaced parallel relation to the aforementioned pivot rod 20 in spaced bushings 26 which are rigidly secured to base 10.

The two blade support bars 14 and 16 are operatively connected for pivotal movement together about their respective rotation axes by means of a pull rod 28 which is pivotally connected at one end to swing arm 18 via pivot hinge 29 and at its other end via a suitable pivot hinge to a relatively short pull arm 30, the latter being rigidly secured to the lower blade support bar 14 an open loading region L, as seen in FIG. 1, is provided whereby to allow for ease of loading of trees into the apparatus, as described hereinafter. In order to prevent undue stressing and deflection of the upper blade support bar 16, the free end of same carries a roller 16a which cooperates with a guide 16b rigidly secured to the base as seen in FIG. 2. During operation, roller 16a bears against guide 16b to absorb some of the load applied to support bar 16 as a result of the delimbing operation.

Each of the blade support bars 14 and 16 is provided with a plurality of lower and upper cutter blades 32 and 32, respectively, arranged to engage and sever limbs on tree trunks passing through said delimber. Each blade support bar 14, 16 has rigidly welded thereto a heavy elongated support plate 34, 36 respectively, each of the latter having that marginal edge remote from the support bar provided with a series of V-shaped notches. The marginal edges defining the notched portions each have a sharp cutter blade 32, 32' extending therealong and rigidly secured thereto by any suitable means whereby corresponding V-shaped notches are defined between said cutter blades 32, 32'. FIG. 8 shows one suitable way of connecting a cutter blade 32, 32 to a support plate 34, although it should be realized that the blades can be directly attached by welding to the support plates. As shown, the blade 32, 32' is secured by a series of screws 38 to an intermediate member 40 located between plate 34 and bracket 41. Blade adjustment screws 42 bear against opposing sides of the intermediate member 40 and by rotating screws 42, each cutter blade 32, 32' may be positioned to and fro relative to its support plate to obtain the best overall cutting effect. Each cutting blade 32, 32' is bevelled along its leading edge to provide a sharp cutting edge 32a whereby to engage and sever limbs from trees which are partially disposed in the V-notches between the blades 32 and moving in the general direction of arrow A relative to the blade as shown in FIG. 8.

- It will be noted from FIG. 4 that the cutter blades 32, 32 of the upper and lower blade support bars are angularly arranged such that when they are in contact with a tree trunk the cutting edges of the respective upper and lower sets of blades 32, 32' lie in planes which are oriented at acute angles a and [3 respectively to the longitudinal axis of the tree trunk. The reason for this is that it is desirable that the cutting edges of the cutter blades 32, 32 meet the limbs of the tree at an acute angle relative to the direction of movement of the tree through the device. This angled relationship promotes a smooth slicing action when the blades encounter the tree limbs and reduces the pulling forces which must be applied to the trees to promote severing.

The V-shaped notches defined between the cutter blades 32 supported on blade support bar 14 are aligned with blades 32 defined on blade support bar 16 so that trees travelling through the machine in the di rection of arrows A in FIG. 1 (which direction is generally at right angles to the elongated blade support bars) will first pass between the blades 32 of the lower leading blade support bar 14 whereby the limbs on the lower portion of the tree trunks are severed with the tree then passing beneath the upper trailing blade support bar 16 whereby its blades 32 complete the operation by severing the limbs from the upper portions of the tree trunks.

It will be noted that the movement of the tree trunks in the direction of arrow A causes a torque to be applied to the cutter blades 32 of the lower leading blade support bar 14 which torque is transmitted via pull arm 30 and pull rod 28 to swing arm 18 which, in turn, applies forces to the upper trailing blade support bar 16 which tend to bring and hold its cutter blades 32 in contact with the upper surfaces of the tree trunks thus effecting delimbing of the upper as well as the lower portions of the moving tree trunks. (Suitable means for supplementing this action are described hereinafter). When the delimber is not in use, the coil torsion spring 24 connected between the swing arm 18 and base 10 brings the swing arm 18 to the upright position such that the various components occupy the relative positions shown in FIG. 2; however, this spring force is immediately overcome by the torsional forces applied by the moving tree trunk when the device is in operation as described above.

While the above described arrangement has been shown to function effectively, greatly improved results can be obtained if additional means are provided to hold the blades 32 of the upper blade support bar 16 in contact with the moving tree trunk during operation. As seen in the drawings, an elongated roller 40 extends transversely of the delimbing apparatus, parallel to, slightly above and rearwardly, relative to a moving tree, of the lower blade support bar 14. Roller 40 is resiliently supported at its opposing ends in suitable bearings 41 which are mounted in upright support posts 42, the latter being rigidly secured to base 10. These bearings are supported on coil compression springs 44 disposed within support posts 42 and which bias roller 40 upwardly at all times. One end of roller 40 is provided with a flanged reel 46 to which one end of a flexible steel cable 48 is attached. The other end of this cable 48 is connected to the upper end of swing arm 18 in such a way that tension on cable 48 is maintained at all times so as to prevent it from jumping off reel 46. This connection includes a weight 50 anchored to the end of the cable 48 and free to move lengthwise within the I tubular swing arm 18. The cable passes through an eyelet 52 in the swing arm for connection to weight 50. when cable 48 is shortened and lengthened, swing arm 18 tends to swing counterclockwise and clockwise as seen in FIGS. 2 or 3. If a situation occurs which would result in undue slack in cable 48, weight 50 simply moves along arm 18 under the influence of gravity to maintain at least some tension in the cable.

In order to cause roller 40 to grip and be rotated by the trunk of a tree moving while in contact with the roller, the latter is provided with a plurality of sharp teeth 60. FIG. 9 shows a typical way of securing these teeth 60 to the roller. The teeth are actually formed in elongated metal strips 62 which are secured longitudinally to roller 40 by bolts or by welding so that the teeth project tangentially outwardly from the roll circumference whereby to provide good engagement of the teeth with a tree trunk. Thus, as trees are pulled through the delimber, the resulting rotation of roller 40 will tension cable 48 and assist in rotating the swing arm 18 around sufficiently as to bring the blades 32 of the upper blade support bar 16 into contact with the tree. The above described action supplements the forces applied to swing arm 18 by pull arm 30 and pull rod 28 as described above and ensures effective delimbing under all conditions. Since roller 40 is spring mounted, the roller is pushed downwardly sufficiently during operation so as to permit good engagement between the blades 32 of the lower support bar 14 and the individual trees; furthermore, the spring mounting limits the amount of torque which the tree can apply to roller 40 thus preventing breakage of cable 48 after the blades 32' of support bar 16 contact the tree.

In operation, the delimber is placed a suitable distance, e.g. 100 feet, ahead of a pile of felled trees. A conventional log skidder is used to tow a small bunch of these trees toward the delimber. The skidder approaches the rear of the delimber and passes it on that side of the delimber which is open as illustrated by arrow D in FIG. 1. After the skidder has gone beyond the delimber a short distance e.g. 6 feet, it shifts the trees inwardly of the open side of the delimber whereby they are located between the upper and lower blade support bars M and 16 and the cutter blades 32, 32' carried thereby. The trees are then dropped onto the lower blade support bar l4 and roller 40. The skidder then moves forwardly about 30 feet or so, depending on the overall length of the trees, at the same time paying out cable from its winch drum. With the skidder properly aligned with the delimber, the winch drum is put into operation whereby to pull the trees through the delimber. As soon as the trees begin to move, the torsional forces described above cause the swing arm 18 to pivot around whereby the cutter blades 32' of the upper blade support bar 16 engage the trees. The trees are then drawn through the delimber whereby the cutter blades 32' 32 of the upper and lower blade support bars l6, 14, respectively sever the limbs L from the trees. Once the trees have been drawn fully through the delimber, the skidder itself moves forwardly and pulls the delimbed trees to a suitable location. The severed branches, of course, merely fall to the ground below the blade support bars and accumulate there. These branches are removed periodically so that they do not interfere with the operation of the delimber. The skidder front end blade can be used to carry out this opera tion since there are no obstructions to hamper sarne i.e. the base of the delimber and the attached anchoring means lie flat on the ground.

The delimber can handle several trees at a time. The operator will, of course, quickly learn from experience the optimum number of trees to be handled each time; this number will depend somewhat on the condition of the trees i.e. number and size of branches, nominal diameter of trunk etc. The delimber itself can be made in different sizes depending on the ranges of tree sizes to be handled.

I claim:

1. Apparatus for delimbing felled trees comprising:

a. a base adapted to be secured in a fixed position;

b. first and second groups of cutter blades,

c. support means attached to said base for supporting said first and second groups of cutter blades therealong, said supporting means for said blades being linearly elongated in a direction transverse to the direction of travel of the trees relative thereto during operation such that the blades are capable of simultaneously engaging a plurality of generally parallel tree trunks in such manner as to sever limbs from said trunks when the latter move longitudinally through said apparatus,

(1. said means supporting said first and second groups of cutter blades being arranged to hold said first and second groups of blades in limb severing engagement with first and second opposing sides, re-

spectively, of said tree trunks as they are moved longitudinally through the delimbing apparatus, whereby to sever limbs from said tree trunks.

2. Apparatus according to claim 1 wherein said means supporting said first and second groups of cutter blades comprise first and second elongated cutter blade supports, respectively, to which the cutter blades are affixed in such a fashion as to effect limb severing when the tree trunks are moved longitudinally through said apparatus generally transversely to the elongated blade supports, at least one of said cutter blade supports being movable in such a way as to bring the cutter blades thereof into limb severing engagement with one of said opposing sides of the moving trunks.

3. Apparatus according to claim 1 wherein the means supporting the first and second groups of cutter blades comprise first and second elongated cutter blade supports, respectively, to which said blades are affixed, both of said cutter blade supports being supported for movement relative to said base, and means operatively connecting said cutter blade supports together such that the forces applied to one of said cutter blade supports by virtue of the tree trunks moving while in engagement with the cutter blades thereof tend to cause the other cutter blade support to move such as to bring its blades into limb severing engagement with the other side of said trunks.

4. Apparatus according to claim 3 wherein said other cutter blade support is mounted on an arm for pivotal movement relative to said base, said one cutter blade support being pivotally mounted to said base, and said means operatively connecting said cutter blade supports together comprising mechanical linkage means.

5. Apparatus according to claim 4 wherein said other cutter blade support is connected at one of its ends to said arm, said cutter blade supports being parallel to one another and being arranged such that they provide a generally open side defining a loading region whereby to permit felled trees which are to be delimbed to be readily positioned between said cutter blade supports.

6. Apparatus according to claim 2 wherein said cutter blade supports are generally horizontally disposed when said base is horizontally arranged. 7. Apparatus according to claim 1 wherein said cutter blades are arranged on said cutter blade supports such that generally V-shaped notches or openings are defined between said blades, the V- shaped notches being arranged such that the tree trunks are partially disposed therein during the delimbing operation. 8. Apparatus according to claim 4 wherein said cutter blades are arranged on said cutter blade supports such that generally V-shaped notches or openings are defined between said blades. 9. Apparatus according to claim 1 wherein said groups of cutter blades are arranged to enable the cutting edges thereof to meet the limbs of the tree at an acute angle relative to the direction of movement of a tree passing through the device. 10. Apparatus according to claim 4 wherein said groups of cutter blades are arranged to enable the cutting edges thereof to meet the limbs of the tree at an acute angle relative to the direction of movement of a tree passing through the device.

11. Apparatus according to claim 2 wherein said cutter blade supports are generally horizontally disposed when said base is horizontally arranged tional means responsive to movement of said tree trunk and operatively connected to assist in pivoting said arm and bring the blades of said other cutter blade support into said limb severing engagement with said other side of said trunk.

13. Apparatus according to claim 12 wherein said additional means includes roller means adapted to engage and be rotated by the moving tree trunk. 

1. Apparatus for delimbing felled trees comprising: a. a base adapted to be secured in a fixed position; b. first and second groups of cutter blades, c. support means attached to said base for supporting said first and second groups of cutter blades therealong, said supporting means for said blades being linearly elongated in a direction transverse to the direction of travel of the trees relative thereto during operation such that the blades are capable of simultaneously engaging a plurality of generally parallel tree trunks in such manner as to sever limbs from said trunks when the latter move longitudinally through said apparatus, d. said means supporting said first and second groups of cutter blades being arranged to hold said first and second groups of blades in limb severing engagement with first and second opposing sides, respectively, of said tree trunks as they are moved longitudinally through the delimbing apparatus, whereby to sever limbs from said tree trunks.
 2. Apparatus according to claim 1 wherein said means supporting said first and second groups of cutter blades comprise first and second elongated cutter blade supports, respectively, to which the cutter blades are affixed in such a fashion as to effect limb severing when the tree trunks are moved longitudinally through said apparatus generally transversely to the elongated blade supports, at least one of said cutter blade supports being movable in such a way as to bring the cutter blades thereof into limb severing engagement with one of said opposing sides of the moving trunks.
 3. Apparatus according to claim 1 wherein the means supporting the first and second groups of cutter blades comprise first and second elongated cutter blade supports, respectively, to which said blades are affixed, both of said cutter blade supports being supported for movement relative to said base, and means operatively connecting said cutter blade supports together such that the forces applied to one of said cutter blade supports by virtue of the tree trunks moving while in engagement with the cutter blades thereof tend to cause the other cutter blade support to move such as to bring its blades into limb severing engagement with the other side of said trunks.
 4. Apparatus according to claim 3 wherein said other cutter blade support is mounted on an arm for pivotal movement relative to said base, said one cutter blade support being pivotally mounted to said base, and said means operatively connecting said cutter blade supports together comprising mechanical linkage means.
 5. Apparatus according to claim 4 wherein said other cutter blade support is connected at one of its ends to said arm, said cutter blade supports being parallel to one another and being arranged such that they provide a generally open side defining a loading region whereby to permit felled trees which are to be delimbed to be readily positioned between said cutter blade supports.
 6. Apparatus according to claim 2 wherein said cutTer blade supports are generally horizontally disposed when said base is horizontally arranged.
 7. Apparatus according to claim 1 wherein said cutter blades are arranged on said cutter blade supports such that generally V-shaped notches or openings are defined between said blades, the V-shaped notches being arranged such that the tree trunks are partially disposed therein during the delimbing operation.
 8. Apparatus according to claim 4 wherein said cutter blades are arranged on said cutter blade supports such that generally V-shaped notches or openings are defined between said blades.
 9. Apparatus according to claim 1 wherein said groups of cutter blades are arranged to enable the cutting edges thereof to meet the limbs of the tree at an acute angle relative to the direction of movement of a tree passing through the device.
 10. Apparatus according to claim 4 wherein said groups of cutter blades are arranged to enable the cutting edges thereof to meet the limbs of the tree at an acute angle relative to the direction of movement of a tree passing through the device.
 11. Apparatus according to claim 2 wherein said cutter blade supports are generally horizontally disposed when said base is horizontally arranged and wherein said cutter blades are arranged on said cutter blade supports such that generally V-shaped notches or openings are defined therebetween and wherein said groups of cutter blades are arranged to enable the cutting edges thereof to meet the limbs of the tree at an acute angle relative to the direction of movement of a tree passing through the device.
 12. Apparatus according to claim 4 including additional means responsive to movement of said tree trunk and operatively connected to assist in pivoting said arm and bring the blades of said other cutter blade support into said limb severing engagement with said other side of said trunk.
 13. Apparatus according to claim 12 wherein said additional means includes roller means adapted to engage and be rotated by the moving tree trunk. 